Recyclable resin-based analogue material for brittle rocks and its application in geomechanical model test

摘要

Geomechanical model test is a common approach in geotechnical and geological research. Analogue materials with appropriate properties are of great importance to the reliability of model test. In this paper, a new type of analogue material composed of coarse aggregate (quartz sand and/or barite sand), fine aggregate (barite powder), and cementitious material (resin) is proposed and its mechanical properties are investigated by orthogonal experiments with more than 300 samples. Three factors, the ratio of coarse to fine aggregate, the ratio of barite sand to coarse aggregate, and the ratio of resin to aggregate, are selected as independent variables and their influence on mechanical parameters of the samples are revealed by range analysis. Multiple linear regression analysis is carried out to establish quantitative relationships between proportions and mechanical parameters. The adjustability of bulk density and E/S ratio (ratio of elastic modulus to uniaxial compression strength) is discussed and effective methodology is proposed. The recycling of the solid waste of samples is also studied experimentally. The application prospect of the proposed analogue material is demonstrated by a successful physical simulation of strain bursting of deep-buried rocks in laboratory. The proposed analogue material meets the widely accepted specifications, and experiments indicate that it possesses several advantages, such as predictability, adjustability, and recyclability, which would significantly facilitate the preparation and improve the reliability of geomechanical model tests.